Well tester



July 26, 1938.

2 Sheets-Sheet 1 Filed March 20, 1937 W M m v Xm M AI. E 7 t 3 b m P 8w. l w E I 9 3 m o 4 m fi \w t V///////7 /4/ A w 1 .r 2 O nu a A 5 RQIIW a July 26, 1938. cox 2,124,766

WELL TESTER Filed March 20, 1 937 2 Sheets-Sheet 2 v 1,. III/l ErnestH.co

[III/III I III/I Patented July 26, 1938 UNITED STATES PATENT orrics WELL'rss'raa, nest 11. Cox, Houston, Tex. Application rum-h so, 1931, SerialNo. 131,995

8 Claims. (01. ass-1) My invention relates to well testers for thepurpose of making a test of the productivity of the formationencountered in well drilling.

It is an object of the invention to provide a construction of welltester which will be operable through a single string of pipe or drillstem and which will be capable of positive action to open and close theinterior of the tester to receive and then cut off a sample of theformation in which the test is made.

-I desire to provide a well tester which may be employed in connectionwith a hole of reduced diameter extended ahead of the main well hole,and ordinarily referred to as a rat hole, and to be operated by a down11 pressure exerted upon the operating stem.

It is a further object of the invention to provide an eflicient means ofsealing the tester against the entrance of fluid under pressure beforethe device is moved to open position.

It is a furtherobject of the invention to provide in connection with atester of this character a means for introducing into the well bore astream of flushing iiuiii when gas under pressure is encountered. i I IIt is a further object of the invention to provide a chamber for thereception 'of a sample of the contents oi the well which may be held inI closed-position while the well is being filled with The inventionresides largely in the particular construction and arrangement oi theparts making up my tester. I

This construction will be more clearly understood through reference tothe drawings and description thereof which follows:

In the drawings, Fig. i is a side view of h;- tester showing the drillstem partly'in central lonm= tudinalsection.

Fig. 21s an enlarged longitudinal section showing the arrangement bywhich the flushing fluidmay be discharged into the well while the testis being made.

Fig. 3 is a transverse section on the'plane M of Fig. 2.

Fig. i is a broken detail taken on the plane t-t of Fig. 3 and showing avalve control discharge opening for the flushing fluid such as may beemployed.

Fig. 5 is a central longitudinal section through the well tester.

Fig. 6 is a side view partly in elevation and partly in sectionillustrating the tester in open position.

Fig. 7 is a transverse section on the plane 1-! of Fig. 6; and r Fig. 8is a similar transverse section on the plane 88 of Fig. 6. i

The construction of the sample receiving por- 5 tion of the invention isdisclosed particularly in Figs. 5 to 8, inclusive. This device isadapted to p be secured to the lower end of a section of pipe I whichmay be drill stem or other pipe. The devce is connected to the drillpipe by means of a 10 coupling 2 of ordinary construction. The upper endofv the tester comprises a nipple 3 threaded at its upper end forconnection with the coupling and having its outer diameter increased toform adjacent the lower end a shoulder 4 against which the compressionspring 5 may hear. The lower distance downwardly within the mandrel andis connected at its lower endwith the exterior thereof through lateralpassages ill. The lower body ll oi the mandrel is reduced in diametersomewhat, as shown at l2 to allow 'the passage of liquid around theoutside of the mandrel and between the same'and the outer sleeve 83.

The sleeve i3 is threaded within the lower end of a head it, said headbeing spaced from the v mandrel and having an inner recess to receivetherings of packing is. Said rings are supported upon a shoulder in thehead and are adapted to be compressed into sealing engagement with theouter surface oi the mandrel by means of a gland 40 it threaded withinthe upper end of the head it.

' The upper end of the head Hi forms a lower shoulder against which thecompression spring 5,

previously referred to, may engage. I contemplate forming a protectivehousing ll about the spring by means of a sleeve of metal threaded atits lower end to the head it and projecting upwardly beyond the springand along the outer surface of the nipple t and fitting slidably againstsaid nipple.

The sleeve 63 extends downwardly from the head I for a suitable distanceand has openings or perforations l8 adjacent the lower end through whichfluid from the well bore may pass.

Above the perforated portion of the sleeve I is of flexible packingmaterial spaced apart by rings 20 of metal or other rigid equivalentmaterial. The lower one of the packing washers I3 issupported upon adownwardly tapered ring 2i, which is in turn supported upon a ring 22screwed upon the outer surface of the sleeve l3. Itwill be noted thatthe outer surface of the head I is tapered downwardly and that thepacking washers is are adapted to. be compressed against the inner wallof the rat hole, the tapered area of the head engaging within the upperportion of the rat hole, thus together forming a seal around the testerwhen it is in operative position at the bottom of the well.

At the lower end of the solid portion H of the mandrel I have screwed acap 23, said cap having an upper shoulder at 24 which limits therelative downward movement thereon of the sleeve i3, the lower end ofsaid sleeve being held against said cap by the spring 5 previouslydescribed. The lower end of the sleeve may have thereon a skirt 2!fltting slidably over the upper portion of the cap 23 and tending toprevent the entrance of sand or sediment thereto.

With the parts of the tester arranged as shown in Fig. 5 the passagesIll leading to the interior of the tester are closed by contact with thesealing rings it. when pressure is exerted upon the drill stemsufilcient to force the mandrel downwardly relative to the sleeve l3 thespring 5 will be compressed and the mandrel will be shoved downwardlyinto the position shown in Fig. 6, with the openings ll exposed belowthe packing rings. In this position fluid from the well may enterthrough the openings i3 in the sleeve and pass upwardly around the solidportion of the mandrel and enter the openings i0 and from thence passupwardly through thepassages 3 and 3, and by raising the ball valve 29may pass upwardly into the chamber 23 within the pipe or drill stem I.

It frequently occurs that when a. test of this kind is made there isfound to be a pressure of gas in the well which tends to blow upwardlythrough the casing and to thus damage the well. To avoid this, itbecomes necessary to pump mud downwardly into the well so as to weightdown the gas within the well and carry away the aerated portion ofthemud into which the gas has entered. In order to accomplish this inconnection with the tester and thus avoid dangerous blowouts I haveprovided means whereby the sample may be retained within the tester anddrill stem and still allow the circulation of mud.

To accomplish this I provide a circulating head 21, .which is threadedat both ends for connection within the drill stem. This head comprises aheavy casting of metal having a central passage 28 therethrough, thelower end of which is partially closed by a plug 30. Said plug isscrewed within the lower end of the circulating head and has arestricted bore 3| longitudinally thereof. Within the upper body of thehead I form a plurality of downwardly extending passages 32. Saidpassages terminate approximate- 1y midway of, the length of the head andare connected with laterally extending branches 33 which discharge intovalve chambers 34. As will be seen from Fig. 4, there is an outlet fromthe valve chamber 34 downwardly at an inclination as is indicated at 31in that flgure.

Thisoutlet discharges to the lower side of the central enlarged portionof the circulating head 21. It will be seen from this construction thatfluid pumped downwardly in the drill stem may pass through the passages32 and 33 to the valve chamber and after passing the valve may be pro-Jected downwardly through the outlet 31 into the well casing 38.

Above the circulating head 31 I screw within the upper portion of thepassage 28 an upwardly extending chamber or passage 39 upon the upperend of which is placed a standing valve preventing the entrance ofliquid thereto from above. Said standing valve is of ordinaryconstruction having a valve cage 40, an inner valve seat 4|, and a ballvalve 42 in said cake and resting upon said seat.

It will be seen that when occasion arises to force mud down through thedrill stem and into the well bore this may be done without interferw ingwith the sample of the formation which has been taken. Fluid circulatingdownwardly through the stem will be shut oil from the tubular extension33 by the standing valve and will be circulated outwardly into the wellbore through the circulating head as described. The sample of formationwhich enters through the tester as described may pass upwardly past thelower ball valve 29 and into the chamber provided by the section of thedrill stem i and the extension tube 33 above the circulating head. Thischamber may be opened when the tester has been withdrawn from the wellandthe sample of well fluid may be found retained within the chamberthus provided.

The advantage of my invention lies in the simple construction wherebythe inlet to the receiving chamber is closely sealed, during theinsertion of the device into the well, by means of the packing rings It.This chamber will, however, be opened to receive the well fluid by therelative'downward movement of the mandrel in the sleeve into position toexpose the entrance openings It. When the test has been made thepressure on the device may be released by'moving the drill 'stemupwardly, thus automatically closing the further entrance of liquid tothe receiving chamber.

There is the further advantage that fluid may be circulated into thewell in case heavy gas pressures are encountered without interferingwith the sample contained within the receiving chamber. I am thusenabled to make a satisfactory test and still be enabled to circulatewhere emergency arises so as to prevent a blowresponse to downwardpressure on said string when said chamber is supported at the-bottom ofthe well, valves adjacent the upper end 'of said chamber to preventdownward passage 'of fluid therein, and means in said string todischarge flushing fluid from said string when said testing .means isbeing operated.

2. Means for testing the productivity of wells including a string ofpipe, a chamber therein ineluding a section of said string and astanding barrel extending upwardly above said section, said chamberbeing normally closed at its lower end'butadapted to be opened toreceive a sample of the well fluid in response to downward pressure onsaid string when said chamber is supported at the bottom of the well,valves adjacent the upper end of said chamber to prevent downwardpassage of fluid therein, and means in said string to discharge flushingfluid from said string when said testing means is being operated.

3. Means for testing the productivity of wells including a string ofpipe, a chamber therein including a section of said string and astanding barrel extending upwardly above said section, said chamberbeing normally closed at its lower end but adapted to be opened toreceive a sample of the well fluid in response to downward pressure onsaid string when said chamber is supported at the bottom of the well, anupwardly opening valve in said chamber, a circulating head in saidstring above said valve to direct flushing fluid from said string, apassage upwardly through said head and a standing valve at the upper endof said passage. 4. A well tester for use in a well having a hole ofreduced diameter at its lower end, including a single string of pipe, atest mandrel at its lower end, an axial passage in said mandrel for ashort distance at its upper end, the lower end of said mandrel beingsolid, a sleeve spaced slightly from said mandrel, there being openingsfrom said passage to the interior of said sleeve and openings insaidsleeve, packing elements in said sleeve normally closing the openings insaid mandrel, means holding said sleeve normally downwardly on saidmandrel, a stop member on said mandrel limiting the downward movement ofsaid sleeve thereon, a packer on said sleeve to engage the upper end ofsaid reduced diameter well hole, said mandrel being movable by pressurerelatively downwardly in said sleeve to move said openings below saidpacking to receive fluid from said sleeve.

5. A well tester for use in a well havinga hole of reduced diameter atits lower end, including a single string of pipe, 0. test mandrel at itslower end, an axial passage in said mandrel for a short distance at itsupper end, the lower end of said mandrel being solid, a sleeve spacedslightly from said mandrel, there being openings from said passage tothe interior 01 said sleeve and openings in said sleeve, packingelements in said sleeve 3 normally closing the openings in said mandrel,means holding said sleeve normally downwardly on said mandrel, a stopmember on said mandrel limiting the downward movement of said sleevethereon, a packer on said sleeve to engage the upper end of said reduceddiameter well hole, said mandrel being movable by pressure relativelydownwardly in said sleeve to move said openings below said packing toreceive fluid from said sleeve, and a valve at the upper end of saidmandrel to prevent the passage of fluid downwardly in said mandrel andsleeve.

6. A well tester including a single string of pipe, a perforated sleeveon the lower end thereof, a packer on said sleeve, a mandrel on saidpipehaving a hollow portion with openings from the .interior to said sleeveand slidable in said sleeve,

means on said mandrel to limit the movement thereon of said sleeve,packing rings in said sleeve normally closing said openings, means tohold said sleeve resiliently downwardly to close said openings, anupwardly opening valve closing the upper end of said hollow portion, andmeans to discharge flushing fluid from said string ofpipe above saidtester.

7. A well tester including a single string of pipe, a perforated sleeveon-the lower end thereof,

a packer on said sleeve, a mandrel on said pipe having a hollow portionwith openings from the interior to said sleeve and slidable in saidsleeve,

means on sald'mandrel to limit the movement thereon of said sleeve,packing rings in said sleeve normally closing said openings, means tohold said sleeve resiliently downwardly to close said openings, anupwardly opening valve closing the upper end of said hollow portion,means to discharge flushing fluid from said string of pipe above saidtester, and a chamber in said string for well fluid between said valveand said flushing fluid discharge means.

8. In a well tester including a single string of pipe,'a testing chamberat the lower end thereof and means to close and open the lower end ofsaid chamber, thecombination of a circulating head in said string abovesaid testing chamber, said head acting to close the passage of fluidupwardly in said string except for a restricted axial passage, a tubeextending upwardly from said passage, a standing valve thereon,discharge passages in said head for fluid from circulating head to thewell.-

ERNEST H. COX.

above said 59

